<div
  data-bind="style:containerStyle,event:{scroll:handleContainerScroll}"
  class="virtual-container"
>
  <div class="virtual-holder" data-bind="style:holderStyle"></div>

  <div class="virtual-content" data-bind="style:contentStyle">
    <!-- ko foreach: { data: displayMembers,as:'member'} -->
    <div data-part="content">
      if you see this message ,the data-part="content" is not set,please set it.
    </div>
    <!-- /ko -->
  </div>
</div>
